One of the most common conditions affecting cats is allergy. In the allergic state, the cat's immune system "overreacts" to foreign substances (allergens or antigens) to which it is exposed. Those overreactions are manifested in three ways. The most common is itching of the skin, either localized (one area) or generalized (all over the cat). Another manifestation involves the respiratory system and may result in coughing, sneezing, and/or wheezing. Sometimes, there may be an associated nasal or ocular (eye) discharge. The third manifestation involves the digestive system, resulting in vomiting or diarrhea.

The anal sacs are located on either side of the anus at the 9 o’clock and 3 o’clock positions; they are positioned just under the skin. They connect to the anus by means of small canal or ducts. Anal sacs produce and store a dark, foul-smelling fluid. These are the same types of organs that a skunk has to scare away its enemies. Although cats can use these for the same purpose, most cats live in an environment that has no enemies. Because the sacs are rarely emptied, the fluid builds up, solidifies, and becomes an ideal environment in which bacteria can grow.

Anemia is defined as a reduced number of red blood cells or hemoglobin, or both. It is a clinical sign, not a specific disease. It is a significant finding because red blood cells, or erythrocytes, are needed to transport oxygen to the tissues. When the total numbers of red blood cells are reduced, there can be insufficient oxygen delivery to vital organs.

Red blood cells are produced in the bone marrow, or hollow core of the bones, by specialized cells. Before being released into circulation, the precursor cells must undergo a specific sequence of steps to reach full maturity. Once released by the bone marrow, the red blood cell lives about 60-70 days in cats.

Bladder stones, more correctly called uroliths, are rock-like collections of minerals that form in the urinary bladder. They may occur as a large, single stone or as dozens of stones the size of large grains of sand or pea gravel.

Although the kidneys and urinary bladder are both part of the urinary system, kidney stones are usually unrelated to bladder stones.

Blastomycosis is a fungal disease caused by the organism Blastomyces dermatitidis. While the first human case was reported in 1898, this disease was not observed in the cat until 1961. During the last 20 years, a number of cases of feline blastomycosis have been reported, and we now know that the disease is more common than originally thought.

Buspirone (trade name BuSpar.) is a drug used by physicians to treat anxiety disorders in humans. Clinical trials with the drug have demonstrated its effectiveness in treating cats with elimination behavior problems (urine spraying). Although its success rate is not 100%, it has been shown to be useful in a large number of cats. One study showed about a 75% reduction in urine spraying in half of the cats studied.

It is not labeled as a veterinary-approved product. Although tested in a large number of cats, it is not approved by the FDA for this purpose. Significant side effects have not been observed, but are always possible. Any abnormal behavior in a cat taking the drug should be reported.

Cardiomyopathy literally means "disease of the heart muscle." This is a disease that occurs in purebred and non-purebred cats of any age. Males and females are equally affected. There are three distinct forms and a variation of one of them.

Cat Scratch Disease (CSD), also known as Cat Scratch Fever, is an infectious disease of humans. Evidence is increasing that the cat becomes infected with the causative organism, but it does not appear to produce disease in the cat. Very little is known or understood about the role as of the cat as a reservoir for this disease.

Cholangiohepatitis is a long and intimidating word that means an inflammation or infection in the gall bladder (cholangitis) and liver (hepatitis). It is a disease that is fairly common in cats of any age.

When a cat has a discharge from its nose that lasts more than 2 months, it is considered chronic. Nasal discharge is classified based on the appearance of the draining fluid. The classification is as follows:

1. The discharge may be thin and clear like water - serous

2. The discharge may be thick and yellow or green in color, similar to pus - purulent

Chylothorax is a relatively uncommon disorder in the cat whereby lymph fluid (chyle) accumulates in the pleural cavity. This small cavity lies between the lungs and the inner lining of the chest wall. Normally, only about a teaspoon of clear fluid is present in this space. The purpose of the fluid is to keep the surface of the lungs slippery so that they don’t adhere to the chest wall.

Coccidiosis is an infection with a one-celled organism; these organisms are classified as protozoa and are called coccidia. Coccidia are not worms; they are microscopic parasites that live within cells of the intestinal lining. Because they live in the intestinal tract and commonly cause diarrhea, they are often confused with worms.

The cornea is the clear, shiny membrane that makes up the surface of the eyeball. It is much like a clear window. To understand the significance of a corneal ulcer, you must first understand how the cornea is constructed.

The cornea is comprised of four layers. The most superficial layer is the epithelium. Actually, this layer is comprised of many, very thin layers of cells. Below the epithelium is the stroma. The next deeper layer is called Descemet's membrane. The deepest layer is the endothelium; it is composed of a single layer of cells. Because all of these layers are clear, it is not possible to see them without special stains and equipment. The cornea must maintain its transparency to ensure clear vision.

The knee joint of the cat is one of the weakest joints of the body. Just as football players frequently suffer knee injuries, the cat also has knee injuries. Fortunately, cruciate ligament injuries are relatively uncommon in the cat.

Cryptococcosis a fungal disease caused by the organism Cryptococcus neoformans. While the first human case was reported in 1894, this disease was not observed in the cat until 1951. Since that time, we have learned a great deal about this common fungal disease of the cat.

The term "cystitis" literally means inflammation of the urinary bladder. Although this term is rather general, there is a common form of cystitis that occurs in male and female cats. This disease is also known as Feline Urologic Syndrome (FUS) or Feline Lower Urinary Tract Disease (FLUTD). It affects the bladder (not the kidneys), resulting in the production of bloody urine that contains microscopic crystals. The cat often urinates frequently, usually with the passage of only a few drops of urine. This is often confused with constipation.

Cytauxzoonosis is a serious, invariably fatal disease of the cat. It occurs when the cat is bitten by a tick; usually Dermacentor variabilis, or the American dog tick, is involved. A single tick bite can successfully transmit the organism to the cat. The domestic cat is thought to be an “accidental” host for this parasite. The natural reservoir for the organism is the bobcat; in this species, the organism may survive for long periods of time.

Dental disease is a common and often overlooked problem in cats. While cavities represent the most common dental disease of humans, cats are more frequently bothered by tartar buildup on the teeth. Tartar accumulation leads to irritation of the gums around the base of the teeth, ultimately leading to exposure of the roots. Potential outcomes of this tooth root exposure include gum infections and tooth loss.

There are two forms of diabetes in cats: diabetes insipidus and diabetes mellitus. Diabetes insipidus is a very rare disorder that results in failure to regulate body water content. Your cat has the more common type of diabetes, diabetes mellitus. This disease is seen on a fairly regular basis, usually in cats 5 years of age or older. Simply put, diabetes mellitus is a failure of the pancreas to regulate blood sugar.

Diarrhea is not a disease; rather, it is a symptom of many different diseases. Many mild cases of diarrhea can be resolved quickly with simple treatments. Rarely, diarrhea is the result of a fatal illness, such as cancer. Even diarrhea caused by mild illnesses may result in death if treatment is not begun early enough to prevent severe fluid and nutrient losses.

Infection of the external ear canal, also called the outer ear, is called otitis externa. When the middle ear and inner ear are involved, these are described as otitis media and otitis interna, respectively.

The term “elimination disorder” is used to describe cats that do not use their litter boxes for urination and/or defecation; instead, these cats eliminate somewhere in the house. Elimination disorders are the most common behavioral problem of cats. Because most owners take pride in their homes, house soiling by the cat can strain the owner-pet relationship to the breaking point. Unfortunately, in some cases, frustrated owners give up their cat to an animal shelter or elect for euthanasia.

Your cat has been scheduled for an endoscopic examination of the gastrointestinal tract. The gastrointestinal tract is composed of the stomach, small intestine, and large intestine (or colon). The purpose of this procedure is to visually inspect the lining of the gastrointestinal tract for the presence of obvious abnormalities and to obtain a small amount of tissue for microscopic study.

An endoscope is a flexible tube that contains fiberoptics. This technology allows study of the gastrointestinal tract and offers the potential for diagnosis of many diseases without exploratory surgery.

The eosinophilic granuloma complex is a group of diseases that appear to be related. They causes are distinct lesions on the skin that respond to the same treatment; this is one of the reasons that they are grouped together as a "complex." The name is somewhat misleading because not all variations of the lesions contain eosinophils (a type of white blood cell).

Eosinophils are normal blood cells that are part of the body's immune system. Their numbers increase in certain diseases, including allergies and parasites. They are also found in high numbers in a few other diseases but are typically not related to cancer.

An esophagostomy tube is a small rubber tube that enters a surgical incision on the side of the neck. Placement of the tube through this incision allows food to enter the esophagus and then flow down into the stomach.. The tube is not placed directly into the stomach.

One of the most common uses of the feeding tube is in management of hepatic lipidosis (“fatty liver” ). Because anorexia can be a significant problem in sick cats, the tube has application in many other situations, as well.

The Feline Immunodeficiency Virus (FIV), often called the Feline AIDS Virus, is an important infectious disease of the cat. It is likened to the AIDS virus which affects humans because of the similarities in the two diseases which result. Fortunately, most viruses are species specific. This is the case with the human AIDS virus and with FIV. The AIDS virus affects only humans, and the FIV affects only cats.

Feline Infectious Anemia (FIA) is a blood disease of cats caused by a microscopic parasite called Hemobartonella felis (H. felis). Because of the organism’s name, this disease is also sometimes called hemobartonellosis. This organism attaches to the surface of the cat's red blood cells, where its presence is eventually detected by the immune system. Once the immune system recognizes the parasite, it attempts to eliminate it by destroying the red blood cells. With destruction of a large number of red cells, anemia may result.

Feline Infectious Peritonitis (FIP) is a progressive, almost always fatal, viral disease of domestic cats. It affects some exotic cats, with the cheetah being particularly susceptible. It does not affect non-feline species, such as dogs.

Feline leukemia virus infection was, until recently, the most common fatal disease of cats. Because we can now protect cats with a leukemia virus vaccine, we are seeing fewer cases of the disease. However, it still remains a major cause of death in cats.

"Leukemia" means cancer of the white blood cells. This was the first disease associated with the feline leukemia virus (FeLV) and, thus, the source of its name. We often use the term "leukemia" rather loosely to include all of the diseases associated with the virus, even though most are not cancers of the blood. This virus causes many other fatal diseases, in addition to leukemia.

Cats are very territorial animals and will fight with other cats to establish territory or to defend existing territory. As a result, fight wounds are common in cats. These wounds frequently result in an infection that can be quite debilitating, especially if left untreated.

One of the most common conditions affecting cats is allergy. In the allergic state, the cat's immune system "overreacts" to foreign substances (allergens or antigens) to which it is exposed. These overreactions are manifested in three ways. The most common is itching of the skin, either localized (one area) or generalized (all over the cat). Another manifestation involves the respiratory system and may result in coughing, sneezing, and/or wheezing. Sometimes, there may be an associated nasal or ocular (eye) discharge. The third manifestation involves the digestive system, resulting in vomiting or diarrhea. The specific response that occurs is related to the type of allergy present.

Giardiasis is an intestinal infection of man and animals caused by a protozoal parasite called Giardia intestinalis. It is widely known as the source of ‘traveler’s diarrhea.” These single-celled parasites are not to be confused with the common intestinal parasites: roundworms, hookworms, and tapeworms.

Giardiasis is a important cause of illness in animals and man. Fortunately, even though the prevalence rate is high in cats and dogs, clinical disease is less common.

Heartworms are 9-11” long worms that live in a cat’s heart or in the arteries going to the lungs (pulmonary arteries). Although they occur commonly in dogs, most people do not consider them a problem for the cat. However, recent studies of cats with heart and respiratory diseases have found an incidence of heartworms that is far greater than we previously thought.

An aural (ear) hematoma is a collection of blood, serum, or a blood clot within the pinna (earflap). When present, the pinna will be very thick. The swelling may involve the entire pinna or it may involve only one area.

When something irritates the ear canal, the cat responds by scratching or shaking the head. Excessive shaking causes blood vessels to break, resulting in bleeding. An understanding of the ear's anatomy makes the sequence of event more logical.

Hepatic lipidosis, also known as fatty liver syndrome (FLS), is one of the most common liver disorders of the cat. It is also seen in horses, dairy cows and rarely in very young puppies. In dogs, however, it is not thought to cause a significant illness. In humans, it is a serious disease which can occur with pregnancy.

Hookworms are intestinal parasites of the cat (and dog). Their name is derived from the hook-like mouthparts they use to anchor to the lining of the intestinal wall. They are only about 1/8" (1-2 mm) long and so small in diameter that they are barely visible to the un-aided eye.

The scientific names for the most common feline hookworms are Ancylostoma tubaeforme and Ancylostoma braziliense. Occasionally, cats will also become infected with the dog hookworm, Ancylostoma caninum.

Contributing Factors
In humans, hypertension is related to several factors, including a stressful lifestyle. Although not all the causes of feline hypertension have been identified, stress does not appear to play a role in the development of this disorder in cats. However, kidney disease and thyroid disease are known to cause feline hypertension and will be described in more detail below.

The thyroid gland is located in the neck and plays a very important role in regulating the body's rate of metabolism. Hyperthyroidism is a disorder characterized by the overproduction of thyroid hormone and a subsequent increase in the metabolic rate. This is a fairly common disease of older cats. Although the thyroid gland enlarges, it is usually a nonmalignant change (benign). Less than 2% of hyperthyroid cases involve a malignancy.

Many organs are affected by this disease, including the heart. The heart is stimulated to pump faster and more forcefully; eventually, the heart enlarges to meet these increase demands for blood flow. The increased pumping pressure leads to a greater output of blood and high blood pressure. About 80% of cats with hyperthyroidism have high blood pressure.

Icterus is also known as jaundice or yellow jaundice. It means that a yellow pigment is found in the blood and in the tissues. It is most easily seen in the gums, the sclerae (white part of the eyes), the skin between the ears and the eyes, and the pinnae (ear flaps). However, if these tissues normally have a dark color, icterus may not be visible.

Inflammatory bowel disease (IBD) is an important and relatively common medical problem of cats. It is not a specific disease; rather, the term IBD represents several processes that are manifested as inflammation of the bowel. It may involve only the small intestine, large intestine, or stomach; in some cases, all parts of the gastrointestinal tract are affected.

Chronic kidney disease is a relatively common disorder in cats, especially geriatric cats. Renal (kidney) insufficiency or renal failure occurs when the kidneys are no longer able to perform their normal function of removing waste products from the blood. The former is the early stage of the latter.

Kidney failure is not the same as the inability to make urine. In fact, most cats with kidney failure are producing large volumes of urine in an attempt to remove the waste products that have accumulated in the blood. This apparent contradiction between the large volume of urine produced and declining kidney function is often a source of confusion for owners.

The colon is a tubular, muscular structure, which represents the termination of the intestinal tract. It is continuous with the rectum. The colon has several functions, such as absorption of water, storage of feces, and defecation (emptying of the bowel). When the muscles in the wall of the colon are stimulated to contract by nerves from the spinal cord, fecal material is pushed out of the body.

Megacolon is a condition of colonic dilation and is a fairly common problem in the cat.

Obstructive and allergic lung diseases affect many cats and are sometimes called asthma, bronchitis, or bronchial asthma. Unfortunately, these diseases are not easily classified and probably represent a variety of lung disorders. They do share a common finding of “hyper-responsive” (over-reactive) airways.

When the airway of the cat is sensitive to certain stimuli, exposure to these agents leads to narrowing of the airways. The inciting agents are usually direct irritants to the airways or things that provoke an allergic response in the respiratory tract. Regardless of the cause, the end-result is the same: muscle spasms in the bronchi (breathing tubes), buildup of mucus, and accumulation of cellular material. In particular, the inability to clear the bronchi of this material leaves the cat susceptible to secondary infections.
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Pancreatitis

The pancreas is an important digestive organ, which has two primary functions:
1) to produce enzymes that help in digestion of food and,
2) to produce hormones, such as insulin. The pancreas is located in the right side of the abdomen near the ribs. Pancreatitis is a disorder of the pancreas that involves an intense inflammatory process. Although pancreatitis occurs less commonly in the cat than in the dog, recent research efforts have demonstrated that it occurs more commonly than previously believed.

Pyothorax is a bacterial infection that develops in the chest cavity, also called the pleural space. This space is located between the lungs and the chest wall. Presence of bacteria in the chest cavity causes white blood cells and fluid to migrate into the pleural space; eventually, pus will begin to accumulate. The presence of fluid in the chest cavity causes a mechanical problem in that it limits the amount of room available for the lungs to expand. As fluid accumulates, the cat tries to compensate by breathing more rapidly. As more and more fluid builds up, the cat is forced to take very shallow breaths. Pain associated with inflammation in the pleural space (pleuritis) may also contribute to shallow breathing. In addition to respiratory difficulties, the infection in the chest releases toxins into the blood stream; this is a further stress on the cat.

Rabies is a viral disease that may infect any warm-blooded animal. Regardless of the initial site of virus introduction into the animal, the virus eventually invades the central nervous system. With rare exception, it is a uniformly fatal disease.

Ringworm is a skin disease caused by a fungus (plural: fungi). Because the lesions are often circular, ringworm was once thought to be caused by a worm curling up in the tissue. However, ringworm has nothing to do with any type of worm.

Ringworm is also known as dermatophytosis. There are four species of fungi that can cause dermatophytosis in cats; however, it is most often caused by the organism called Microsporum canis. The Microsporum canis organism is so well adapted to cats that up to 20% of cats are thought to be asymptomatic carriers, meaning they have the organism but show no outward signs.
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Roundworm Infection (Ascariasis)

Roundworms are the most common intestinal parasite of the cat. Infection rates in kittens are thought to approach 100%. They can represent an important cause of illness, and even death, in kittens. As their name implies, these are large-bodied round worms, averaging about 3-6 inches (8-15 cm) in length. They do not attach to the wall of the intestine, as do hookworms. Instead, they are literally "swimming" within the intestine. Return to top ˆ

Seizures

Seizures are one of the most frequently seen neurological problems in cats. A seizure is also known as a convulsion or fit. A seizure represents a period of abnormal brain wave activity that leads to a variety of clinical signs.

Tapeworms are intestinal parasites of the cat (and dog). Because they are classified as cestodes, they belong to a different family than the hookworms and roundworms (called nematodes). Several types of tapeworms are known to infect cats; Dipylidium caninum is by far the most common.

The tapeworm uses its hook-like mouthparts for anchoring to the wall of the small intestine. Eventually, adult tapeworms may reach several inches in length. As the adult matures, individual segments (proglottids) break off from the main body of the tapeworm and pass into the cat’s feces. Return to top ˆ

Thyroidectomy

Thyroidectomy is the surgical removal of one or both lobes of the thyroid gland. This surgery is performed on cats with hyperthyroidism.
The thyroid gland is divided into two lobes, each about ½ ” long and very flat. They are located on each side of the trachea (windpipe). When they are normal, they are high in the neck at the level of the larynx. As they enlarge due to hyperthyroidism, they move down the neck toward the chest.

Toxoplasmosis is an infectious disease caused by a one-celled parasite called Toxoplasma gondii. It is a prevalent parasite of cats throughout the world, although other species can become infected. The cat is unique in that it is the definitive host of the parasite, meaning that the organism must pass through the cat to complete all stages of its life cycle.

Cats may become infected with upper respiratory viruses that resemble the common cold in humans. By "upper respiratory," we mean that the infection is limited to the nose, throat, and trachea; the eyes may also become involved. Lower respiratory tract infections involve the lungs.

Vomiting is not a specific disease; it usually is a sign of a number of different diseases. In general, the veterinarian must to decide whether the cause of vomiting is more likely to fall into a particular category of causes.

2. Vomiting caused by a disorder within the gastrointestinal tract or abdomen. Examples of these disorders include intestinal parasites, dietary indiscretion, pancreatitis, inflammatory diseases of the stomach and/or intestinal tract, and cancer.

The anal sacs are located on either side of the anus at the 9:00 and 3:00 positions; they are positioned just under the skin. They connect to the anus by means of small canals, or ducts. Anal sacs produce and store a dark, foul-smelling fluid. These are the same types of organs that a skunk has to scare away its enemies. Although dogs can use these for the same purpose, most dogs live in an environment that has no enemies. Because the sacs are rarely emptied, the fluid builds up, solidifies, and becomes an ideal environment in which bacteria can grow.

Anemia is defined as a reduced number of red blood cells or hemoglobin, or both. It is a clinical sign, not a specific disease. It is a significant finding because red blood cells, or erythrocytes, are needed to transport oxygen to the tissues. When the total numbers of red blood cells are reduced, there can be insufficient oxygen delivery to vital organs.

Bladder stones, or uroliths, are rock-like collections of minerals that form in the urinary bladder. Uroliths may occur as a large, single stone or as dozens of smaller stones. Individual stones can vary in size from tiny stones, which can be voided in the urine stream to larger stones the size of a golf ball.

This is a term that is synonymous with the more scientific term "Gastric Dilatation/Volvulus." It is often called GDV. It means that a dog's stomach distends with gas to the point that the dog goes into shock and may die.

Chronic kidney disease is a relatively common disorder in dogs, especially geriatric dogs, although it can occur in young dogs. It occurs when the kidneys are no longer able to perform their normal function of removing waste products from the blood. This is not the same as the inability to make urine. In fact, most dogs with renal disease are producing large volumes of urine. This disparity between the large volume of urine produced and declining kidney function are often a source of confusion for owners.

Intestinal coccidiosis is an infection with a one-celled organism; these organisms are classified as protozoa and are called coccidia. Coccidia are not worms; they are microscopic parasites that live within cells of the intestinal lining. Because they live in the intestinal tract and commonly cause diarrhea, they are often confused with worms.

The trachea, also known as the windpipe, is an important structure that connects the throat to the lungs. It serves the purpose of directing air into the respiratory tract.

The normal trachea is tubular. It maintains its shape because of a series of rings made of cartilage. These rings do not completely encircle the trachea. Instead, they go from the 2 o'clock to 10 o'clock positions. The remainder of the trachea composed of a flexible membrane that joins the ends of the cartilage rings.

The cornea is the clear, shiny membrane that makes up the surface of the eyeball. It is much like a clear window. To understand a corneal ulcer, you must first understand how the cornea is constructed.

Canine coronavirus is one of the infectious causes of enteritis, or intestinal inflammation, in puppies and dogs. The first reported outbreaks of this disease came in the 1970’s. It is highly contagious between susceptible dogs but, fortunately, most dogs recover without complication. Because of this, it not generally considered a serious pathogen (infectious agent) of dogs.

The knee (stifle) joint of the dog is one of the weakest in the body. Just as athletes (football players, in particular) frequently suffer knee injuries, the dog also has knee injuries. The knee joint is relatively unstable because there is no interlocking of bones in the joint. Instead, the two main bones, the femur and tibia, are joined with several ligaments. When severe twisting or excessive extension of the joint occurs, the most common injury is a rupture of the anterior cruciate ligament (ACL). When it is torn, instability occurs that allows the bones to move in an abnormal fashion in relation to one another. When this happens, it is not possible to bear weight on the leg without it collapsing.

Cushing's Disease is a disorder in which the adrenal glands overproduce certain hormones. Another medical term disease for this disease is hyperadrenocorticism. There are two adrenal glands, one on each side of the abdomen; they are located just above each kidney.

The spinal cord is one of the most important and most sensitive organs in the body. If it is traumatized, its cells will not regenerate; injuries usually result in permanent damage. Therefore, the spinal cord is protected in a very special fashion. It goes through a bony canal within the spine where it is surrounded by protective bone everywhere except over the disks. This extreme protection reflects its importance and its fragility.

Mange is a parasitic skin disease caused by microscopic mites. Two different types of mange mites are significant in dogs. One type lives just under the surface of the skin, while the other type resides in the hair follicles. Although both types of mites share some similar characteristics, there are also important differences. It is important not to confuse the two types of mange because they have different causes, treatments, and prognoses.

Dental disease is a common and often overlooked problem in dogs. While cavities represent the most common dental disease of humans, dogs are more frequently bothered by tartar buildup on the teeth. Tartar accumulation leads to irritation of the gums around the base of the teeth, ultimately leading to exposure of the roots. Potential outcomes of this tooth root exposure include gum infections and tooth loss.

There are two forms of diabetes in dogs: diabetes insipidus and diabetes mellitus. Diabetes insipidus is a very rare disorder that results in failure to regulate body water content. Your dog has the more common type of diabetes: diabetes mellitus. This is a fairly common disorder and is most often seen is dogs 5 years of age or older. There is a congenital form that occurs in puppies, but this is not common.

Diarrhea is not a disease; rather, it is a symptom of many different diseases. Many mild cases of diarrhea can be resolved quickly with simple treatments. Others are the result of fatal illnesses, such as cancer. Even diarrhea caused by mild illnesses may become fatal if treatment is not begun early enough to prevent severe fluid and nutrient losses.

The heart has four chambers. The upper chambers are called atria (singular: atrium), and the lower chambers are called ventricles. In addition to the upper and lower chambers, the heart is also considered to have a right and a left side.

Blood flows from the body into the right atrium. It is stored there for a few seconds, then pumped into the right ventricle. The right ventricle pumps blood into the lungs, where it receives oxygen. It flows from the lungs into the left atrium; it is held here for a few seconds before going into the left ventricle. The left ventricle contains the largest muscle of the heart so the blood can be pumped out to all parts of the body.

Dilated cardiomyopathy (DCM) means that the heart muscle, called the myocardium, becomes much thinner than normal. In particular, the thick muscle wall of the left ventricle is affected. The pressure of the blood inside the heart allows this thinned wall to begin to stretch, resulting in a much larger left ventricular chamber. Therefore, the two characteristics of dilated cardiomyopathy are a heart wall that is much thinner than normal and a chamber that is much larger than normal.

The prostate (commonly mispronounced as "prostrate") is a gland located near the neck of the urinary bladder of male dogs. The urethra passes through it shortly after leaving the bladder. The purpose of the prostate is to produce some of the fluids found in normal canine semen.

Canine distemper is a contagious viral disease of dogs. It was a fairly common disease in the United States until the introduction of effective vaccines in the 1960’s. In some parts of the world, it remains an important and devastating disease.

Infection of the external ear canal (outer ear) by bacteria or yeast, is one of the most common types of infections seen in dogs. We call this otitis externa. Some breeds, such as Cocker piels and Miniature Poodles, seem more prone to ear infections, but they may occur in any breed.

Ehrlichiosis is an infectious disease of dogs. It first gained attention as a significant disease when military dogs returning from Vietnam during the 1970's were found to be infected. The disease seems to be particularly severe in German Shepherd dogs and Doberman pinchers.

An esophagostomy tube is a small, soft rubber tube that enters a surgical incision on the side of the neck into the esophagus. It allows you to syringe food into the esophagus. From there it will flow down into the stomach. The tube is not placed directly into the stomach.

One of the most common conditions affecting dogs is allergy. In the allergic state, the dog's immune system "overreacts" to foreign substances (allergens or antigens) to which it is exposed. These overreactions are manifested in three ways. The most common is itching of the skin, either localized (one area) or generalized (all over the dog). Another manifestation involves the respiratory system and may result in coughing, sneezing, and/or wheezing. Sometimes, there may be an associated nasal or ocular (eye) discharge. The third manifestation involves the digestive system, resulting in vomiting or diarrhea. The specific response that occurs is related to the type of allergy present.

Successful flea control has two aspects. Fleas must be controlled on your dog, and fleas must be controlled in your dog's environment. Since cats and dogs share the same fleas, the presence of a cat in your dog's environment can make flea control much more difficult.

One of the most common conditions affecting dogs is allergy. In the allergic state, the dog's immune system "overreacts" to foreign substances (allergens or antigens) to which it is exposed. These overreactions are manifested in three ways. The most common is itching of the skin, either localized (one area) or generalized (all over the dog). Another manifestation involves the respiratory system and may result in coughing, sneezing, and/or wheezing. Sometimes, there may be an associated nasal or ocular (eye) discharge. The third manifestation involves the digestive system, resulting in vomiting or diarrhea.

Your dog has been scheduled for an endoscopic examination of the gastrointestinal tract. The gastrointestinal tract is composed of the stomach, small intestine, and large intestine (or colon). The purpose of this procedure is to visually inspect the lining of the gastrointestinal tract for the presence of obvious abnormalities and to obtain a small amount of tissue for microscopic study.

An endoscope is a flexible tube that contains fiberoptics. This technology allows study of the gastrointestinal tract and offers the potential for diagnosis of many diseases without abdominal surgery.

Heartworm disease (dirofilariasis) is a serious and potentially fatal disease in dogs. It is caused by a worm called Dirofilaria immitis.

Heartworms are found in the heart and large adjacent vessels of infected dogs. The female worm is 6 to 14 inches (15 to 36 cm) long and 1/8 inch (5 mm) wide; the male is about half the size of the female. One dog may have as many as 300 worms.

An aural (ear) hematoma is a collection of blood, serum, or a clotted blood within the pinna (earflap). When present, the pinna will be very thick. The swelling may involve the entire pinna or it may involve only one area.

Hemorrhagic gastroenteritis (HGE) is a fairly common disorder of dogs that is characterized by the sudden development of vomiting and/or diarrhea. The vomitus and the diarrhea may contain variable amounts of bright, red blood or dark, digested blood.

Hip dysplasia (HD) is defined as a deformity of the coxofemoral (hip) joint that occurs during the growth period. Hip dysplasia is a hereditary condition that creates a poorly fitting hip joint. As the dog walks on this joint, arthritis will eventually develop, causing pain in the joint. The degree of lameness that occurs is usually dependent upon the extent of arthritic changes in the hip joint.

Dogs have many parasites, both internal and external. Internal parasites are those which live in the various organs inside the dog's body. Some of the internal parasites migrate through a number of different organs. Intestinal parasites are internal parasites that live in the small or large intestine (colon). External parasites, such as fleas, ticks, and mites, live on the outside of the body.

The thyroid gland is one of the most important glands in the body. It is located in the neck near the trachea and is composed of two lobes, one on each side of the trachea (windpipe). This gland is controlled by the body’s master gland, the pituitary gland, located at the base of the brain.

The thyroid gland regulates the rate of metabolism. If it is hyperfunctional, metabolism speeds up. If it is less functional than normal, metabolism slows down. The latter is the basis for the clinical signs of hypothyroidism.

Icterus is also known as jaundice or yellow jaundice. It means that a yellow pigment is found in the blood and in the tissues. It is most easily seen in the gums, the sclerae (white part of the eyes), and the pinnae (ear flaps). However, if these tissues normally have a dark color, icterus will probably not be seen.

The word “hepatitis” is a nonspecific medical term describing any inflammatory process of the liver. A number of different diseases can cause hepatitis. One infectious cause is Infectious Canine Hepatitis, or (ICH). This viral disease was first recognized as a unique disease of dogs in 1947.

Inflammatory bowel disease (IBD) is an important and relatively common medical problem of dogs. It is not a specific disease; rather, the term IBD represents several processes that are manifested as inflammation of the bowel. It may involve only the small intestine, large intestine, or stomach; in some cases, all parts of the gastrointestinal tract are affected.

Canine infectious tracheobronchitis, or “kennel cough,” is an important respiratory disorder because it is highly contagious between dogs. A number of different infectious agents may be involved with this disease. It is characterized by bouts of nonproductive (dry) coughing lasting from days to even weeks.

Leptospirosis is an important and relatively complex infectious disease of dogs. It can affect almost all species of warm-blooded animals, including humans.

Recognition of the disease is sometimes difficult because clinical signs will vary depending upon the particular serovar, or strain, of the Leptospira organism that has infected the dog. At least ten different serovars are known to infect dogs. Most commercial vaccines contain antigens (proteins) which stimulate immunity against the icterohemorrhagiae and canicola serovars. The incidence of disease caused by these two serovars has decreased because of vaccines; however, other serovars are becoming more common in the animal population.

A lick granuloma is an open sore on the skin caused by and perpetuated by constant licking. It is generally located on one of the legs, especially near the carpus (wrist) joint. Typically, the hair will be licked off and the area will be either raw and weeping or thickened and scar-like.

Lick granulomas usually begin with an itching or tingling sensation on the leg. The dogs respond to that by licking; this may serve to further increase the itching or tingling. Very shortly, a viscous cycle develops, creating a habit much like a child sucking its thumb. Even if the problem that initiated the itching or tingling sensation is gone, the habit of licking continues.

This is a disease that occurs at the lumbosacral junction. The term “lumbo” refers to the lumbar vertebrae. These are the bones in the lower part of the spinal column. The term “sacral” refers to the sacrum, which is the part of the spine that joins the lumbar spine and the pelvis. Changes that occur in the vertebrae, supporting ligaments or adjacent disks can all contribute to this pathologic narrowing of the spinal cord canal.

The patella, or kneecap, should be located in the center of the knee joint. The term "luxating" means out of place or dislocated. Therefore, a luxating patella is a kneecap that moves out of its normal location.

Lyme Disease (not Lyme's Disease) is caused by a spirochete called Borrelia. A spirochete is a type of bacterium. It is transmitted to dogs through the bite of a tick. Once in the blood stream, it is carried to many parts of the body. It is especially likely to localize in joints.

It was first thought that only a few types of ticks could transmit this disease, but now it appears that several common species may be involved.

Lyme Disease is named after the city in which it was first discovered, Old Lyme, Connecticut. Thus, it is called “Lyme Disease” and not “Lyme’s” Disease.

The heart has four chambers. The upper chambers are called atria (singular: atrium), and the lower chambers are called ventricles. The heart is also divided into right and left sides.

Blood flows from the body into the right atrium. It is stored there for a few seconds, then pumped into the right ventricle. The right ventricle pumps blood into the lungs where it receives oxygen. It flows from the lungs into the left atrium where it is held a few seconds before going into the left ventricle. The left ventricle is surrounded by the largest and strongest of the heart muscles. This large muscle is necessary to pump blood to all parts of the body.

Each side of the heart has a valve to keep blood from going backward from the ventricles to the atria. The valve between the left atrium and left ventricle is called the mitral valve. Because of the very large pressures created when the left ventricle contracts and the eventual process of “wearing out,” the mitral valve becomes leaky in many dogs.

Because this is a progressive disease, we assign each dog to one of four stages based on clinical signs, historical findings, and x-ray findings. Stage 1 is the earliest stage of mitral valvular disease. Stage 4, the final stage, is the presence of life-threatening heart failure.

The pancreas is a vital organ that lies on the right side of the abdomen. It has two functions: 1) to produce enzymes which help in digestion of food and, 2) to produce hormones, such as insulin. When the pancreas becomes inflamed, the disorder is called pancreatitis. It is a disease process that is seen commonly in the dog. There is no age, sex, or breed predisposition.

There are two main forms of acute (sudden onset) pancreatitis: 1) the mild, edematous form and, 2) the more severe, hemorrhagic form. A few dogs that recover from an acute episode of pancreatitis may continue to have recurrent bouts of the acute disease, known as chronic, relapsing pancreatitis. The associated inflammation allows digestive enzymes to spill into the abdominal cavity; this may result in secondary damage to surrounding organs, such as the liver, bile ducts, gall bladder, and intestines.

Canine parvovirus (CPV) infection (sometimes called “parvo”) is a relatively new disease that struck the canine population in 1978. The classic signs are vomiting and bloody diarrhea. Because of the severity of the disease and its rapid spread through the canine population, CPV has aroused a great deal of public interest. The virus that causes it is very similar to feline distemper, and the two diseases are almost identical. Therefore, it has been speculated that the canine virus is a mutation of the feline virus. However, that has never been proven.

The virus has a selective effect on the most rapidly dividing cells of the body. For this reason, the lining of the small intestine and the cells of the bone marrow are most severely affected.

Ringworm is a skin disease caused by a fungus (plural: fungi). Because the lesions are often circular, it was once thought to be caused by a worm curling up in the tissue. However, there is no truth to that; it has nothing to do with a worm.

There are four fungal species affecting dogs which can cause the disease that we call ringworm. These may also affect humans. The fungi live in hair follicles and cause the hair shafts to break off at the skin line. This usually results in round patches of hair loss. As the fungus multiplies, the lesions may become irregularly shaped and spread over the dog's body.

Dogs have many parasites, both internal and external. Internal parasites are those which live in the various organs inside the dog's body. Some of the internal parasites migrate through a number of different organs. Intestinal parasites are internal parasites that live in the small or large intestine (colon). External parasites, such as fleas, ticks, and mites, live on the outside of the body.

Roundworms represent a common intestinal parasite of the dog. They are also sometimes called ascarids. Typically, they are large, heavy-bodied worms and average 3-5 inches in length. They live in the dog's intestines, consuming partially digested food. In contrast to the behavior of the hookworm, the roundworm does not attach to the intestinal wall; rather, this worm literally swims in its food.

Dogs have many parasites, both internal and external. Internal parasites are those which live in the various organs inside the dog's body. External parasites, such as fleas, ticks, and mites, live on the outside of the body.

Mange is a parasitic skin disease caused by microscopic mites. Two different types of mange mites are significant in dogs. One type lives just under the surface of the skin, while the other type resides in the hair follicles. Although both types of mites share some similar characteristics, there are also important differences. It is important not to confuse the two types of mange because they have different causes, treatments, and prognoses.

Seizures are one of the most frequently seen neurological problems in dogs. A seizure is also known as a convulsion or fit. A seizure represents a period of abnormal brain wave activity that leads to a variety of clinical signs.

Staph is a commonly used abbreviation for Staphylococcus, a group of bacteria commonly found on the skin. Dermatitis is a term that means that the skin is inflamed.

Staph is a normal resident of the skin of animals and humans; however, it is considered an opportunist. As long as the skin is healthy, Staph is dormant. But once the skin is irritated, Staph can invade the area and multiply rapidly.

The most common tapeworm of dogs (and cats) is called Dipylidium caninum. This parasite attaches to the small intestinal wall by hook-like mouthparts. Adult tapeworms may reach 8 inches (20 cm) in length. The adult worm is actually made up of many small segments about 1/8 inch (3 mm) long. As the tail end of the worm matures, the terminal segments break off and pass into the stool. Occasionally, the mobile segments can be seen crawling near the anus or on the surface of a fresh bowel movement. These segments look like grains of rice and contain tapeworm eggs; the eggs are released into the environment when the segment dries. The dried segments are small (about 1/16", or 2 mm), hard and golden in color. These dried segments can sometimes be seen stuck to the hair around the dog's anus.

Plaque is a gummy substance that forms on the teeth within a few hours after a meal. Within 24 hours, plaque hardens into tartar.

Tartar is harmful in two ways. First, it serves as a place where bacteria can reside and multiply in the mouth. There is substantial scientific evidence that bacteria from tartar enter the blood stream and are deposited in various organs. Heart and kidney disease can result. Second, tartar builds up at the gum line. As the tartar deposit gets larger, it pushes the gums away from the roots of the teeth. Eventually, the teeth will loosen and fall out.

The tonsils are much like lymph nodes (lymph glands). There are two of them, and they are located in the back of the throat. When they are normal, they are not easily seen because they reside in crypts (pouches). Like lymph nodes, their job is to fight infection. When they are doing this, they often become infected themselves and will enlarge.

Von Willebrand's disease (VWD) is the most common inherited bleeding disorder of both man and animals. It is caused by a deficiency in the amount of a protein needed to help platelets (a blood cell used in clotting) seal broken blood vessels. The deficient protein is called von Willebrand factor antigen.

Whipworms are intestinal parasites of the dog. They parasitize the lower intestine (cecum and colon) and cause signs related to intestinal irritation. Infection with whipworms can be significant because they are one of the more pathogenic intestinal parasites found in the dog.

They are small, about 1/4" (45 to 75 mm) long, and have a characteristic “whip” or “lash” at one end. After the worm burrows into the intestine, it is this “whip” that causes damage to the lining of the bowel. The tip of the “lash” is able to slash and shred tissue. The worm then feeds on the blood and damaged lining of the intestine.